In fluid flow, the character of the flow can be determined by the Reynolds number, Re, which is a dimensionless quantity that can be expressed in terms of the speed v of the fluid, the density ρ (mass per unit volume) of the fluid, the viscosity η of the fluid, and a length D which is characteristic to the flow. Re can be expressed in the form Re = kvηaρbDc, where k, a, b, and c are dimensionless constants. What must be the values of b, c, and d? The dimensions of viscosity are [M]/[L][T]. The period P of oscillation of a pendulum (the time interval needed to complete one full oscillation) can be expressed in terms of the mass m of the plumb bob, the length l of the string, and the acceleration due to gravity, g, as P = kmb1cgd, where k, b, c, and d are dimensionless constants. What must be the values of b, c, and d?